Article I, section 5, of the U.S. Constitution provides that "Each House [of Congress] may determine the Rules of its proceedings, punish its members for disorderly behavior, and, with the concurrence of two-thirds, expel a member." Censure is a form of discipline used by the Senate against its members (sometimes referred to as condemnation or denouncement). A formal statement of disapproval, a censure does not remove a senator from office. Since 1789 the Senate has censured nine of its members.
The United States Constitution gives each house of Congress the power to be the judge of the “elections, returns, and qualifications of its own members” (Article I, section 5). Since 1789 the Senate has carefully guarded this prerogative and has developed its own procedures for judging the qualifications of its members and settling contested elections.
The Constitution grants Congress the sole power to declare war. Congress has declared war on 11 occasions, including its first declaration of war with Great Britain in 1812. Congress approved its last formal declaration of war during World War II. Since that time it has agreed to resolutions authorizing the use of military force and continues to shape U.S. military policy through appropriations and oversight.
Article I, section 5, of the U.S. Constitution provides that each house of Congress may "punish its members for disorderly behavior, and, with the concurrence of two-thirds, expel a member." Since 1789 the Senate has expelled only 15 members.
The Senate has a long history of using the filibuster—a term dating back to the 1850s in the United States—to delay debate or block legislation. Unlimited debate remained in place in the Senate until 1917, when the Senate adopted Rule 22 that allowed the Senate to end a debate with a two-thirds majority vote—a procedure known as "cloture." In 1975 the Senate reduced the number of votes required for cloture from two-thirds (67) to three-fifths (60) of the 100-member Senate.
Under the Constitution, the House of Representatives has the power to impeach a government official, in effect serving as prosecutor. The Senate has the sole power to conduct impeachment trials, essentially serving as jury and judge. Since 1789 the Senate has tried 20 federal officials, including three presidents.
Congress has conducted investigations of malfeasance in the executive branch—and elsewhere in American society—since 1792. The need for congressional investigation remains a critical ingredient for restraining government and educating the public.
The Constitution provides that the president "shall nominate, and by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other public Ministers and Consuls, Judges of the Supreme Court, and all other Officers of the United States… (Article 2, Section 2)." The Senate has always jealously guarded its power to review and approve or reject presidential appointees to executive and judicial branch posts.
The Senate is governed by the Constitution, a set of standing rules, precedents established in the course of the legislative process, and special rules of procedure adopted by statute for particular types of legislation. These rules determine how bills and resolutions are moved towards passage, the structure of Senate committees, how debate proceeds on the chamber floor, and how members cast votes.
The Constitution gives the Senate the power to approve, by a two-thirds vote, treaties made by the executive branch. The Senate has rejected relatively few of the hundreds of treaties it has considered, although many have died in committee or been withdrawn by the president. The Senate may also amend a treaty or adopt changes to a treaty. The president may also enter into executive agreements with foreign nations that are not subject to Senate approval.
The Senate takes action on bills, resolutions, amendments, motions, nominations, and treaties by voting. Senators vote in a variety of ways, including roll call votes, voice votes, and unanimous consent.